From: Mike Bayer <mike_mp@zzzcomputing.com>
Date: Tue, 17 Mar 2009 15:09:49 +0000 (+0000)
Subject:     - Fixed SQLite reflection methods so that non-present
X-Git-Tag: rel_0_5_3~4
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3ecf84f5adb428f814cd18b47ac65d133112cbf0;p=thirdparty%2Fsqlalchemy%2Fsqlalchemy.git

- Fixed SQLite reflection methods so that non-present
      cursor.description, which triggers an auto-cursor
      close, will be detected so that no results doesn't
      fail on recent versions of pysqlite which raise
      an error when fetchone() called with no rows present.
---

diff --git a/CHANGES b/CHANGES
index 503031d411..3e1c6f9ecd 100644
--- a/CHANGES
+++ b/CHANGES
@@ -112,6 +112,13 @@ CHANGES
       or dialects.   There is a small performance penalty
       which will be resolved in 0.6.  [ticket:1299]
 
+- sqlite
+    - Fixed SQLite reflection methods so that non-present
+      cursor.description, which triggers an auto-cursor
+      close, will be detected so that no results doesn't
+      fail on recent versions of pysqlite which raise 
+      an error when fetchone() called with no rows present.
+      
 - postgres
     - Index reflection won't fail when an index with 
       multiple expressions is encountered.
diff --git a/lib/sqlalchemy/databases/sqlite.py b/lib/sqlalchemy/databases/sqlite.py
index 8b46132f3e..77eb30ff81 100644
--- a/lib/sqlalchemy/databases/sqlite.py
+++ b/lib/sqlalchemy/databases/sqlite.py
@@ -439,7 +439,8 @@ class SQLiteDialect(default.DefaultDialect):
         else:
             pragma = "PRAGMA "
         qtable = quote(table_name)
-        cursor = connection.execute("%stable_info(%s)" % (pragma, qtable))
+        cursor = _pragma_cursor(connection.execute("%stable_info(%s)" % (pragma, qtable)))
+            
         row = cursor.fetchone()
 
         # consume remaining rows, to work around
@@ -457,7 +458,7 @@ class SQLiteDialect(default.DefaultDialect):
             pragma = "PRAGMA %s." % preparer.quote_identifier(table.schema)
         qtable = preparer.format_table(table, False)
 
-        c = connection.execute("%stable_info(%s)" % (pragma, qtable))
+        c = _pragma_cursor(connection.execute("%stable_info(%s)" % (pragma, qtable)))
         found_table = False
         while True:
             row = c.fetchone()
@@ -496,7 +497,7 @@ class SQLiteDialect(default.DefaultDialect):
         if not found_table:
             raise exc.NoSuchTableError(table.name)
 
-        c = connection.execute("%sforeign_key_list(%s)" % (pragma, qtable))
+        c = _pragma_cursor(connection.execute("%sforeign_key_list(%s)" % (pragma, qtable)))
         fks = {}
         while True:
             row = c.fetchone()
@@ -524,7 +525,7 @@ class SQLiteDialect(default.DefaultDialect):
         for name, value in fks.iteritems():
             table.append_constraint(schema.ForeignKeyConstraint(value[0], value[1], link_to_name=True))
         # check for UNIQUE indexes
-        c = connection.execute("%sindex_list(%s)" % (pragma, qtable))
+        c = _pragma_cursor(connection.execute("%sindex_list(%s)" % (pragma, qtable)))
         unique_indexes = []
         while True:
             row = c.fetchone()
@@ -542,7 +543,11 @@ class SQLiteDialect(default.DefaultDialect):
                     break
                 cols.append(row[2])
 
-
+def _pragma_cursor(cursor):
+    if cursor.closed:
+        cursor._fetchone_impl = lambda: None
+    return cursor
+        
 class SQLiteCompiler(compiler.DefaultCompiler):
     functions = compiler.DefaultCompiler.functions.copy()
     functions.update (